Mechanical ventilation is a method of mechanically assisting or replacing spontaneous breathing when patients cannot do so. One type of ventilation system employs the use of an endotracheal or tracheostomy tube secured into a patient's upper respiratory tract. Gas is mechanically delivered to the patient via the tube. In many cases, mechanical ventilation is used in acute settings such as an intensive care unit for a short period of time during a serious illness. Currently, the main form of mechanical ventilation is positive pressure ventilation, which works by increasing the pressure in the patient's airway and thus forcing additional air into the lungs. To aid in the treatment of ventilated patients, aerosol medicines are aspirated in situ through an access point in the ventilator system. This process is manual, requiring the medical professional to deliver the aerosols on a regular basis.
Bronchodilator and corticosteroid medications for the treatment of reversible airway obstruction are often delivered via inhalation to the lower respiratory tract in both spontaneously breathing and mechanically ventilated patients. The devices typically used for delivery of aerosols to ventilated patients are small-volume nebulizers and pressurized metered-dose inhalers. Small-volume nebulizers and metered-dose inhalers can effectively deliver aerosols in a ventilator model and aerosol delivery can be significantly improved when a proper technique of administration is followed. To enhance lung deposition of aerosols from metered-dose inhalers, several accessory devices have been developed.
The accessory devices most commonly used to deliver aerosols from metered-dose inhalers into ventilator circuits are inline non-chamber devices and inline holding chambers. The advantage of a holding chamber inserted in the ventilator circuit is that the actuated aerosol cloud is retained within the chamber and hence impaction of the drug within the ventilator circuit is reduced.
Goals of this invention include reducing healthcare costs and improving patient safety by automatically administering medication to mechanically ventilated patients.